Global Patent Index - EP 1079514 A1

EP 1079514 A1 20010228 - Frequency synthesizer comprising a phase loop

Title (en)

Frequency synthesizer comprising a phase loop

Title (de)

Frequenzsynthesizer mit einer Phasenschleife

Title (fr)

Synthétiseur de fréquence à boucle de phase

Publication

EP 1079514 A1 20010228 (FR)

Application

EP 00402323 A 20000821

Priority

FR 9910798 A 19990826

Abstract (en)

The frequency synthesizer comprises a block (13) for the determination of real gain of voltage-controlled oscillator (1) on the basis of measured parameters, voltage and frequency, and the delivery of signal representative of real gain. The synthesizer also comprises means for an input of modulation signal between the phase comparator (7) of the phase-locked loop (PLL) and the modulation branch (34) with a divider (38) by real gain (KVCO), a digital-analogue converter (40), and an adder (42). A compensation block (50) generates a signal on the basis of modulation signal for input to the feedback loop (9) upstream of divider (8) by N, in a manner to annul the modulation of signal at the output of voltage-controlled oscillator. The sythesizer also comprises a local oscillator (3) connected to one input of the phase comparator (7), the other input connected to the output of voltage-controlled oscillator via the feedback loop (9), and a low-pass filter (5). The gain determination block (13) contains a sampler (15) for voltage measure at two frequencies, an analogue-digital converter (17), and a computing unit (19) for the computation of real gain (KVCO) of voltage-controlled oscillator (VCO). The block (13) also comprises a temperature sensor, a memory table of VCO gain as a function of temperature, and a control unit for the delivery of real gain of VCO as a function of measured temperature and the gain values stored in memory table. The block (13) also function of operating time, and a control unit for the delivery of real gain of VCO as a function of multiplier (52) by 2.pi, an accumulator (54), I and Q (in-phase and quadrature) signals generator (56), first and second digital-analogue converters (58,60) for I and Q signals, respectively, mixers (62,64), a phase-shifter (66) by pi/2 of VCO output signal, and an adder (68).

Abstract (fr)

L'invention concerne un synthétiseur de fréquences à boucle de phase comportant des moyens (13) de détermination du gain réel de l'oscillateur commandé en tension (1) à partir d'au moins un paramètre de mesure, ces moyens (13) de détermination étant aptes à délivrer un signal représentatif du gain réel de l'oscillateur commandé en tension (1). Des moyens (30,32,34,38,40,42) sont prévus pour introduire un signal de modulation entre le comparateur de phase (7) de la boucle de phase et l'oscillateur (1) commandé en tension de ladite boucle de phase. Par ailleurs des moyens (50) de compensation de modulation sont prévus pour préparer à partir du signal de modulation un signal de compensation et pour introduire celui-ci dans la boucle de retour (9) en amont d'un compteur diviseur (8) disposé dans celle-ci, de manière à annuler la modulation du signal de l'oscillateur commandé en tension. <IMAGE>

IPC 1-7

H03C 3/09

IPC 8 full level

H03C 3/09 (2006.01); H03L 7/093 (2006.01); H03L 7/10 (2006.01); H03L 7/187 (2006.01); H03L 7/189 (2006.01)

CPC (source: EP US)

H03C 3/0941 (2013.01 - EP US); H03C 3/095 (2013.01 - EP US); H03C 3/0975 (2013.01 - EP US); H03C 3/0983 (2013.01 - EP US); H03L 7/189 (2013.01 - EP US)

Citation (search report)

Designated contracting state (EPC)

AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

DOCDB simple family (publication)

EP 1079514 A1 20010228; CN 1286532 A 20010307; FR 2798019 A1 20010302; FR 2798019 B1 20020816; JP 2001094422 A 20010406; SG 109429 A1 20050330; US 6441690 B1 20020827

DOCDB simple family (application)

EP 00402323 A 20000821; CN 00124079 A 20000825; FR 9910798 A 19990826; JP 2000251859 A 20000823; SG 200004833 A 20000825; US 64536000 A 20000825